Safety lock

ABSTRACT

A safety lock having a latch bolt and at least one key-operated bolt both movable to an unlocking position by turning of a single key. Combination tumbler plates are located on opposite sides of an operating plate connected to the key-operated bolt. The tumbler plates are constructed to be moved to a releasing position, permitting movement of the operating plate, regardless whether the key is inserted from one or the other side of a box in which the elements of the lock are mounted. The key-operated bolt is moved to the unlocking position during turning of the key in one direction and means are provided to move the latch bolt to its unlocking position during further turning of the key in the one direction without further withdrawing the key-operated bolt.

[ 1 July4,1972

I54] SAFETY LOCK Rene Alfredo Billino, Lope de Vega 135, Saenz Pena, Argentina [22] Filed: Aug. 26, 1970 [21] Appl.No.: 67,150

[72] Inventor:

1,135,192 12/1968 GreatBritain ..70/417 Great Britain ..70/352 Germany France ..70/401 Primary ExaminerRobert L. Wolfe Attorney-Michael S. Striker [5 7] ABSTRACT A safety lock having a latch bolt and at least one key-operated bolt both movable to an unlocking position by turning of a single key. Combination tumbler plates are located on opposite sides of an operating plate connected to the key-operated bolt. The tumbler plates are constructed to be moved to a releasing position, permitting movement of the operating plate, regardless whether the key is inserted from one or the other side of a box in which the elements of the lock are mounted. The key-operated bolt is moved to the unlocking position during turning of the key in one direction and means are provided to move the latch bolt to its unlocking position during further turning of the key in the one direction without further withdrawing the key-operated bolt.

7 Claims, 7 Drawing Figures PATENTEDJUL 41972 SHEEI 10F 2 I:/E.E

INVENTOR. 954/: mm! HIM W BY /lr 4% w PATENTED 4 1973 3,613,830 SHEET 20F 2 I INVENTOR. pg: mayo mun/0 BY 174 [M SAFETY LOCK The present invention refers to a novel, original and practical safety lock, especially meant to be used in substitution for common locks, on doors and the like, with the advantage of assuring absolute inviolability, due to the use therein, of a system of tumbler plates, normally employed on locks of safety boxes, in combination with cylindrical bolts, also of the kind used on safety boxes.

The novelty includes the combination, in a unit of sizes and shape similar to those of common locks, of a system of Keyoperated bolts and a latch bolt, with the advantage of allowing the bolt mechanism to be operated from either side of the box, with one key.

It is relevant to point out that, until now, although it has been tried to make combinations of this kind, in none of them has it been possible to obtain to operate the safety mechanism from either side of the box; in some cases, two keys were necessary, and in others, since it was impossible to operate the lock from both sides, it had to be placed so as to use it only from the inside or the outside.

The double key system was inconvenient, since it compelled the user to carry along a set of keys for each door on which he had a lock of that kind, so that if the use of such mechanisms had spread, each user would have had to carry along a large number of keys, rather big and heavy.

The solution obtained with this invention surmounts such inconveniences, since it allows to operate the mechanism from one side or the other, with just one key.

From the mechanical point of view, this has been achieved by locating the operating device of the Key-operated bolt in 9 central position, between two sets of tumbler plates of the combination, which on one side, have their combination inverted in respect of that of the opposite side, so that, by operating the key, which will be double-wing, in an inverted position, the mechanism may be operated, from either side of the box.

In this way, maximum safety and absolute convenience are obtained regarding transportation of the key, which is of small size and much similar in appearance to common keys.

It is well known that, at present, the bolts of the locks commonly used, are made of hard or artificially hardened material, to prevent cutting of the bolts by burglars, by means of saws or other tools.

Obviously, the use of such metals means considerable increase in the costs of production, and in fact, the hardness required to assure immunity is not always obtained, especially if it is kept in mind that modern industry supplies day after day, increasingly efficient saws.

In our case, in order to assure that the bolts can not be sawed off, a simple and practical resource is used, which consists simply, of making the bolts in the form of tubular jackets rotating on the respective mounting pins, so that if someone tries to cut them, the jacket rotates following the movement of the saw, which in this way, cannot work.

Besides, a novel, original and practical arrangement has been foreseen in this invention, for guiding the tumbler plates which form the safety combination of the unit and which are displaced through the operating action of the respective key.

At present, the guiding and retention of the combination plates, in safety locks, is not effective, since anyone, being more or less an expert, by using a suitable tool, may reach the springs which tend to hold such plates in position, and in such case, it is possible to cause them to rotate to idle position, in which the operating plate for the Key-operated bolt may be freely displaced, allowing displacement of the bolt.

Such inconvenience is eliminated according to this invention, on the basis of a special mounting of the abovementioned lates. p Another of the novelties introduced by this invention lies in a simple, original, new and practical arrangement tending to allow retraction of the latch bolt, with the same key of the lock, without pushing the front ends of the Key-operated bolts rearwardly beyond the surface of the front plate.

It is a well known fact that common locks and even those generally called safety locks, were vulnerable when the door was closed only with the bolt, since it was then possible to cause the bolt to move, with any similar key, due to the circumstance that the safety combination did not work when the bolts were drawn back.

According to the present invention, the proposed arrangement maintains the safety conditions of the lock, even if only the bolt thereof is engaged, since even the movement of the bolt requires the operative medium, i.e. the key, to meet certain conditions, which means that its construction should correspond to the combination given to the mechanism commanding the bolt, so that any other different key cannot open even the bolt, therefore the safety is absolute.

To achieve this, the plate which is joined to the Keyoperated bolts, is formed by integration with two pieces placed one against the other, of which one may be displaced with respect to the other, when the Key-operated bolts are drawn back, this movable plate including a supplemental tooth, in which the key engages to determine its displacement. This same plate carries fixed thereon the means to move a lever which leads the latch bolt to its withdrawn position, said lever being mounted on the cover of the lock in such a way as to conveniently establish its operative connection with said moving means.

So that this invention may be clearly understood and there should be no hindrance in putting it into practice, it will be described in detail hereunder, referring to the illustrating drawings annexed, in which:

FIG. 1 illustrates in a front view, a preferred form of the mechanism of the safety lock object of the present invention, without taking into account the cover of the lock, and without illustrating the lever causing the latch bolt to draw back.

FIG. 2 is a transversal section of the lock illustrated in FIG. 1, such section being made in coincidence with the location of the mechanism of the safety plates, in order to show clearly the central location of the operating plates for the bolts.

FIG. 3 is a front view of the key used in the lock object of this invention, where it is possible to remark the form of execution of the teeth corresponding to the small tumbler plates of the safety combination.

FIG. .4 illustrates in perspective one of the rotatablebolt, showing in dotted lines the position of a saw which has no influence on said bolt, due to the fact that the latter is rotatable.

FIG. 5 is a front elevation view of the rotatable bolt shown in FIG. 4.

FIG. 6 illustrates in a front view the mechanism of the lock, without the small tumbler plates of the safety combination, showing the possibility to displace one of the plates which being superposed form the operating means for the bolt, and illustrating likewise the lever which, being tiltably connected to the cover of the box of the lock, forms the means of command for the latch bolt to drawn back.

FIG. 7 is a vertical section of the arrangement illustrated in FIG. 6.

In all the figures, the same reference numbers point to equal or corresponding parts.

Referring to the illustrative drawings attached hereto, 1 shows the box of the lock, on which is mounted the latch bolt 2, with its operating nut 3.

Under the bolt mechanism is located reciprocable operating plate 4 carrying the bolts 5, 6, which protrude in the locking position beyond the front of the lock, this plate being situated between the sets 7, 8 oftumbler plates sheets 9 forming the safety mechanism. The tumbler plates are provided with cutouts 10, into which safety clasp 11 extends. A spring 12 is connected to each of the tumbler plates, tending to maintain them in their correct position.

The small tumbler plates, so as to be able to use the key from either side of the box, will be made in such a manner that the combination, on one of the sides of the sliding plate, will be inverted in respect of the one on the other side, and on the key 13, the wings or bolts l4, 15 will be fonned in such an arrangement, that the grooves of the combination are inverted in respect of those of the opposite side.

By means of this type of assembly, when the key has been introduced in the hole 16, provided with a guide 17 in order to avoid a mistaken introduction, upon moving the key, occurs as relevant, the advance or withdrawal of the bolts 4 and 5.

So as to prevent the lock from being violated by cutting the bolts 4 and 5 these bolts comprise as shown: FIGS. 4 and 5, a cylindrical member 18 which is fixed on the front border of the plate 4, a tubular element or jacket 19 rotatingly mounted on said member 18; the tube or jacket is made of hard or artificially hardened metal, and in case someone wishes to act on it with a saw or analogous tool 20, it will rotate on the axial member holding it, thus preventing all possibilities of cut.

Obviously, the assembly of the rotary jacket is mounted that it will never displace itself axially.

So as to avoid that by using suitable tools it might be possible to displace the small tumbler plates 9 of the combination, to a position allowing free sliding of the bolts 4, 5, the proposed lock provides an important innovation. In fact, from plate 4 protrudes the small projection 21, which penetrates in the cut outs of the small plates 9, which form, as we have already seen, the safety combination, such small sheets being held in their working position by means of the combination of the springs 12, the guiding pins 22, 23 and the open ended slots 24, as well as the slot 25.

As it may be appreciated clearly from the drawing of FIG. 1, the slot 24 extends from the upper edge of the small plates, while the groove 25 is adjacent to the lower edge thereof, one extending parallel to the other and each on one side with respect to the location plane of the small column 21, so that even by destroying the springs and one of the guides, it is still impossible to cause the small plates to turn, thus preventing that the command of the bolts, 4, 5 formed by plate 4, might be moved.

In order to achieve the operation of withdrawal of the latch bolt of the lock, with the own key thereof, without drawing back beyond the surface of the front plates, the bolts 4 and 5, this invention provides a simple, original and highly efficient arrangement, which appears clearly illustrated in FIGS. 6 and 7, as will described hereunder.

The bolt 2 of the lock has in its area normally located inside the box, a slot 26 normal to the longitudinal axis of said bolt, and a pin 27 extends through and is freely sliding along the slot 26. The pin 27 is fixed to one of the ends of an elongated lever 28, the opposite end 29 of which is rotatingly connected to the cover 30 of the box of the lock by means of a riveted pin or similar element 31, such lever having in its middle, a cut 32 in which is lodged a pin 33, solidary with plate 34 superposed on plate 4 and which in combination with it, forms the assembly unit of the bolts 5, 6, as we have already seen. The plates 34 and 4, have teeth common in this type of safety lock, as has been shown with references 35 and 36, but besides, plate 34 will have an additional set of teeth 37 which in turn will cooperating with a set of teeth especially incorporated in the key, illustrated in FIG..6 with a dotted line.

The operation of this mechanism is extremely simple, to retract the bolts 4 and 5, the key engages in the teeth 35, for the first half turn, and 36 for the second half turn, the bolts remaining withdrawn in the latter case; if in these conditions the key is still turned, the engagement of said special set of teeth occurs, such teeth 37 taking on plate 34, which is displaced with respect to plate 4 above it, while said plate 4 remains stationary; the movement of plate 34, through the pin 33, is transmitted by the lever 28, and latter through its small pin 27 lodged in the groove 25 of the latch, causes the withdrawal thereof.

It is to be noted that if the key used lacks said special teething, it will in no case engage the complementary teeth 37 and therefore, only with the respective key will it be possible to operate the bolt of the lock. In consequence, if the user closes the door only with the bolt, he will also enjoy absolute safety.

I claim:

1. In a safety lock, a combination comprising a box having a face plate and a pair of opposite side plates; a latch bolt reciprocably arranged in said box between a locking position in which a portion of the latch bolt projects beyond said face plate and a withdrawn unlocking position; biasing means cooperating with said latch bolt for yieldably holding the latter in said locking position; at least one key-operated bolt reciprocably arranged in said box between a locking position in which a front portion thereof projects beyond said face plate and a withdrawn position in which the front end thereof is flush with said face plate; an operating plate in said box connected to the rear end of the key-operated bolt for reciprocation with the same and having along one edge thereof a set of teeth; a second plate superimposed on said operating plate reciprocable therewith and relative thereto and provided on an adjacent edge with an identical set of teeth and 'at least one additional tooth; a pair of aligned keyholes in said opposite side plates of said box adjacent said edges of said plates; a key insertable from either side of said box into said keyholes and having key bits arranged for engagement with said teeth in both plates to move during turning of said key in one direction said plates in a direction for moving said key-operated bolt to its withdrawn position and to engage during further turning of said key said additional teeth on said second plate to move the latter in said direction relative to said operating plate; and operating means connected to said latch bolt and cooperating with said second plate to move said latch bolt to said withdrawn position during movement of said second plate in said direction relative to said operating plate.

2. A combination as defined in claim 1, wherein said operating means comprise a lever pivotally mounted at one end on one of said side plates, connecting means connecting the other end of said lever to said latch bolt, and means on said second plate for engaging said lever intermediate the ends thereof during movement of said second plate in said direction relative to said operating plate to thereby tilt said lever in a direction which moves said latch bolt to said withdrawn position.

3. A combination as defined in claim 2, wherein said connecting means comprises a slot in said latch bolt extending transversely to the direction of reciprocation thereof and a pin fixed to and projecting from said other end of said lever into said slot.

4. A combination as defined in claim 1, and further comprising tumbler plate means arranged in said box on opposite sides of said superimposed plates, said tumbler plate means being movable by said key from a locking position preventing movement of said superimposed plates to a releasing position permitting such movement.

5. A combination as defined in claim 4, wherein said tumbler plate means comprise two groups of tumbler plates respectively arranged on opposite sides of said superimposed plates and constructed to be moved to said releasing position regardless whether the key is inserted from one or the other of said side plates of said box into said key holes.

6. A combination as defined in claim 1, wherein said keyoperated bolt comprises a cylindrical member fixed to said operating plate and a single cylindrical sleeve rotatably mounted on said cylinder.

7. A combination as defined in claim 6, wherein said cylindrical sleeve is made from hardened material. 

1. In a safety lock, a combination comprising a box having a face plate and a pair of opposite side plates; a latch bolt reciprocably arranged in said box between a locking position in which a portion of the latch bolt projects beyond said face plate and a withdrawn unlocking position; biasing means cooperating with said latch bolt for yieldably holding the latter in said locking position; at least one key-operated bolt reciprocably arranged in said box between a locking position in which a front portion thereof projects beyond said face plate and a withdrawn position in which the front end thereof is flush with said face plate; an operating plate in said box connected to the rear end of the key-operated bolt for reciprocation with the same and having along one edge thereof a set of teeth; a second plate superimposed on said operating plate reciprocable therewith and relative thereto and provided on an adjacent edge with an identical set of teeth and at least one additional tooth; a pair of aligned keyholes in said opposite side plates of said box adjacent said edges of said plates; a key insertable from either side of said box into said keyholes and having key bits arranged for engagement with said teeth in both plates to move during turning of said key in one direction said plates in a direction for moving said key-operated bolt to its withdrawn position and to engage during further turning of said key said additional teeth on said second plate to move the latter in said direction relative to said operating plate; and operating means connected to said latch bolt and cooperating with said second plate to move said latch bolt to said withdrawn position during movement of said second plate in said direction relative to said operating plate.
 2. A combination as defined in claim 1, wherein said operating means comprise a lever pivotally mounted at one end on one of said side plates, connecting means connecting the other end of said lever to said latch bolt, and means on said second plate for engaging said lever intermediate the ends thereof during movement of said second plate in said direction relative to said operating plate to thereby tilt said lever in a direction which moves said latch Bolt to said withdrawn position.
 3. A combination as defined in claim 2, wherein said connecting means comprises a slot in said latch bolt extending transversely to the direction of reciprocation thereof and a pin fixed to and projecting from said other end of said lever into said slot.
 4. A combination as defined in claim 1, and further comprising tumbler plate means arranged in said box on opposite sides of said superimposed plates, said tumbler plate means being movable by said key from a locking position preventing movement of said superimposed plates to a releasing position permitting such movement.
 5. A combination as defined in claim 4, wherein said tumbler plate means comprise two groups of tumbler plates respectively arranged on opposite sides of said superimposed plates and constructed to be moved to said releasing position regardless whether the key is inserted from one or the other of said side plates of said box into said key holes.
 6. A combination as defined in claim 1, wherein said key-operated bolt comprises a cylindrical member fixed to said operating plate and a single cylindrical sleeve rotatably mounted on said cylinder.
 7. A combination as defined in claim 6, wherein said cylindrical sleeve is made from hardened material. 